Blower for heat treating furnace



Aug. 12, 1941. T. W. MUNI- ORD BLOWER FOR HEAT TREATING FURNACE Filed Oct. 9, 1959 f I l Patented Ang. 12, 1941 1, 2,252,673

UNITED STATES' PATENT OFFICE Theodore W. Munford, l Ottawa Hills, Ohio, assignor to Surface Combustion Corporation, Toledo, Ohio, a corporation of New York Application October 9, 1939, Serial No. 298,538

3 Claims. (Cl. 308-77) The present invention relates to a blower for rate of heat transfer from the tube to the instirring up or circulating the atmosphere in a serted portion, it is preferred that the contact be furnace chamber wherein articles are being andiscontinuous such as if afforded, for example, by

nealed or otherwise heat treated. In blowers of squaring the inserted portion. The lower end of this type the fan shaft bearing nearest the fany 5 the shaft portion Il is surrounded by a heat abtends to become overheated due to the conduction sorbing seal comprising a series of circumferenof heat along that portion of the fan shaft which tial grooves and ridges 26 formed in the upper projects into the furnace chamber. It is there- -part of a hub 21 whichv houses the bearing 2U.

fore the object of the present invention to provide I-t will be understood that heat at the lower end a blower of such construction that the tendency A1,0 ofthe shaft portion l1 is absorbed and conducted of the fan shaft bearing to overheat shall be reaway b-y the ridges 26. Lubricant is supplied to duced to a minimum. the bearing 20 by a pressure grease tube 28.

In the accompanying drawing wherein the pre- Secured to the shaft section I8 for rotation ferred form of the invention is showntherewith is the impeller or runner 30 of a cen- Fig. lis a vertical section through the improved 1 5 trifugal pump comprising a circular casing 3| blower, a portion of the furnace base being also having a central bottom inlet 32 for cooling shown in outline; medium, the casing being supported by a sleeve Fig. 2 illustrates on a somewhat larger scale a 33 which is detachably secured to the underside feature shown in Fig. l, and of the hub' 2'i. A packing 34 within the sleeve Fig. 3 is a more or less diagrammatic represen- 20 prevents cooling fluid from flowing into saidhub. tation of the type of furnace with which the in- Extending upwardly from the pump casing' is a vention has special utility. circumferential row of fluid` discharge tubes 35 The furnace illustrated in Fig. 3 comprises a whose upper ends are bent toward the hub 2l to base l0, a removable heating hood Il, an inner discharge thereagainst.

cover l2 and a stool I3 on which the work to be 25 Carried by and preferably integral with the heat treated iS Supported. The blower fan is structure 22 is a container 36 adapted to hold indicated at I4, it being noted that the fan shaft, a, supp1y 0f cooling liquid, the cooling liquid level generally ldatd at l5, eXtelldS through the being above the inlet 32, it being noted that the furnace base. side walls 38 of the container extend upwardly Referring now more particularly to Fig. 1. there 30 inte engagement with the depending wen 25 of is provided in the furnace base an upright sleeve the Cap 23 to form a, dosed Space above the conl5 through Which the fan Shaft I5 extends ,into tainer. The hub 21 of the cap preferably carries the furnace chamber, the shaft being prov1ded a trough 39 which receives Cooling liquid ds with ffl driving pulley I9 at its lower end' HOW' charged from the tubes 35, it being understood ever 1t Wm b.e understood that the shaft may be 35 that when the trough is full the liquid overflows Otherms? qrlven' The upper bearmg fo? the and drops back into the container 36. The prishaft 1s indicated at 20 and the lower bearing at mary purpose of the trough is to aord a Substarb 2 I' The Supportmg means for the bearmgs com' tial degree of protection to the bearing 20 in case rises a lower member 22 surmounted by a cap g3 adapted to be secured to the underside of the 40 th lgohfftlacrel 'lftls trllyatg furnace base l0 as by bolts 24 extending through fpet f t t 3s t th the rim of the cap. The cap has a depending cirou 51de 'me of he con amer 1S exposed O e cular wall 25 provided with a bottom flange to Surroundmg atmosphere the hqmd m the con which the member 22 is detachably Secured* tainer will ordinarily be maintained sufficiently It is prefrred that the upper portion n of the 45 cool to obviate the necessity of special cooling as shaft I5 sneu net be send but tubular and that by OWmg fresh @001mg llquld mio the @Ontwerit be made of a material whose heat conductivity t MOTOVGT dependmg frhom tfe Pump clasmg 3l is substantially less than that of the lower shaft 1S 1 clrcular. bams QI' Sklrt 38 spaced mwadly from the adJacent side walls 38 of the container I8. More articularl the upper shaft portion p y for insuring that liquid above the pump shall flow rtion is preferably made of heat resisting alloy 50 ggd the lower portion of ordinary steel, the two downwardly along the relatlvely cool s1de Walls 38 portions being Welded together at their abutting t0 a point adjacent the bottom of the container ends. The lower shaft portion may project a, before flowing to the pump inlet 32. Webs or fins short distance into the upper portion as indicated 29 on the outside walls of the container also asat I8 but in such case, in order to reduce the 5o sist in dissipatng heat from the container walls and also serve to add strength to the structure 22, it being noted that said webs extend vertically.

A closed cooling system of the kind described has special utility in steel mills because of the minimum attention required and because instead of using regular mill water which is likely to be dirty the container 36 may be lled with clean water with or without a non-freeze solution as conditions may require.

40 indicates a breather pipe in the space above the normal liquid level in container 36 and 4| a sight glass for observing the level of the liquid. The cooling liquid may be replenished by removing a plug 42 at the upper sightglass connection.

From the foregoing description it will be seen that the present invention provides a cooling sysem which is relatively simple and well adapted for its intended purpose.

What I claim is:

l. In combination, a support adapted to be secured to the underside of a furnace chamber and having a hub depending therefrom, walls depending from said support to form a container for cooling liquid, a shaft extending upwardly through the bottom of the container and through and beyond said hub for projection into said chamber and having at its upper end a fan for stirring up gases in said chamber, a shaft bearing housed by said hub, and means housed by said walls for drawing cooling liquid from said container and for delivering the same about said hub for cooling the latter, whereby to cool said bearing, said means comprising a hollow body having an inlet facing the bottom of said container, a skirt depending from said body for causing liquid above said body to flow between the skirt and the adjacent walls of the said container before reaching said inlet, and a rotary member housed by said body and connected to said shaft for rotation therewith for drawing liquid into said body.

2. In apparatus of the class described, the combination of a drive shaft having an extension for insertion into a heated chamber' through a bottom wall thereof for driving a device within the chamber, a container adapted to hold a body of cooling liquid, a cover for the container for closing oif the same from the surrounding atmosphere, said cover being adapted for securement to said wall outside of said chamber, said shaft extending upwardly into the container and through and beyond said cover to form said extension, a bearing for the shaft, a housing wherein said bearing is positioned, said housing depending from said cover, and means for drawing liquid from the container and for discharging the same about said housing for cooling the latter whereby to maintain said bearing relatively cool.

3. In apparatus of the class described, the combination of a drive shaft having an extension for insertion into a heated chamber through a bottom wall thereof for driving a device within the chamber, a container adapted to hold a body of cooling liquid, a cover for the container for closing off the same from the surrounding atmosphere, said cover being adapted for securement to said wall outside of said chamber, said shaft extending upwardly into the container and through and beyond-said cover to form said extension, a bearing for the shaft, a housing wherein said bearing is positioned, said housing depending from said cover, a pump for drawing liquid from said container and comprising a rotary element secured to said shaft and a casing for said element, means depending from said housing for supporting said casing, and means carried by said casing for discharging liquid from the latter about said housing for cooling the latter whereby to maintain said bearing relatively cool.

THEODORE W. MUNFORD. 

